The invention relates to hand-held hedge shears with a driving motor, comprising a gripping housing with a rear handle, wherein a gripping part of the rear handle is rotatable about the longitudinal axis thereof and is lockable in the rotational position thereof by means of a locking element, wherein an operating switch lever for the driving motor is arranged on the rotatable gripping part, and wherein the operating switch lever acts by means of a sliding element and a transmission element on a switch unit for the rotational speed position of the driving motor, wherein the sliding element is guided on the locking element in a manner sliding in the direction of the longitudinal axis.
For safety reasons, hand-held hedge shears are used two-handedly. For this purpose, a rear handle with an operating switch lever for the driving motor and a front handle with a safety switch lever for the two-handed operation are provided. In the case of an electric driving motor, the latter can only be put into operation if at the same time one hand is used to actuate the safety switch lever of the front handle and the other hand is used to actuate the operating switch lever of the rear handle.
For certain applications, a fixedly predetermined arrangement of both handles and of the associated switch levers is inexpedient, since, for example when working overhead, the hedge shears has to be held in an unergonomic position for actuation of the operating switch lever, on the one hand, and of the safety switch lever, on the other hand. In order, under this aspect, to expand the range of use of the hedge shears, embodiments are known, in which a gripping part of the rear handle is mounted rotatably about the longitudinal axis thereof in relation to the gripping housing and is lockable in the rotational position thereof by means of a locking element. By unlocking the locking element, the user can bring the gripping part, including the operating switch lever attached thereto, into the desired rotational position and can lock the gripping part there, which results in improved ergonomics for the guiding of the hedge shears for the particular use situation.
In a previously known constructional form, a continuous bearing tube, which is connected fixedly to the gripping housing and on which the gripping part together with the operating switch lever is rotatably mounted, is provided. By means of the bearing tube, which is connected at both ends thereof to the gripping housing, a stiff and portable construction is obtained. However, the bearing tube requires considerable construction space. Since, in addition, to enable a good grip, the cross section of the rotatable gripping part may not be configured to be of unlimited size, there is only little space between the bearing tube and the rotatable gripping part for additional structural elements to be arranged in the gripping part.
The abovementioned construction space situation is further intensified by certain hedge shears being equipped with a “gripping extension”. In this case, an additional safety switch lever is arranged at the rear end of the gripping housing, and, for two-handed operation, can be used as an alternative to the safety switch lever of the front handle. This is expedient in particular when working overhead. The transmission element of the additional, rear safety switch lever has to be guided through the rotatable gripping part. The same also applies to a mains cable which may be present. In the above-described constructional form, the mains cable and also the abovementioned transmission element of the rear safety switch lever are guided through the bearing tube.
In addition, an operative connection also is to be produced between the operating switch lever and a switch unit. The switch unit serves to realize a certain switch logic which allows the electric driving motor to be started only if, in addition to the operating switch lever, one of the two safety switch levers is also actuated. The same expediently also applies in the case of an internal combustion engine as the driving motor. According to the prior art, for the operative connection between the operating switch lever and the switch unit, a sliding element is provided, the sliding element being mounted on the bearing tube in a manner sliding in the direction of the longitudinal axis and being displaced linearly by the operating switch lever being pressed in. The linear displacement movement of the sliding element is transmitted to the switch unit via a suitable transmission element.
It follows from the above considerations that, in the previously known embodiment, the construction space is very confined and leaves virtually no more room for additional components. In particular, a blocking lever for blocking the operating switch lever cannot be arranged on the rotatable gripping part, since a blocking lever of this type would collide with the central bearing tube.